Techwiki:Win32k/LDEVOBJ

This struct match windows XP

typedef struct _LDEV_WIN32K 
{
  /* 0x0000 */   _LDEV_WIN32K * nextldev;
  /* 0x0004 */   _LDEV_WIN32K * prevldev;                 
  /* 0x0008 */   UNICODE_STRING DeviceName;               
  /* 0x000C */   ULONG         levtype;                   
  /* 0x0010 */   ULONG         cRefs;                     
  /* 0x0014 */   ULONG         unk_014;                   
  /* 0x0018 */   void *        pGdiDriverInfo;            
  /* 0x001C */   ULONG         ulDriverVersion;           
  /* 0x0020 */   ULONG         unk_020;                    
  /* 0x0024 */   PFN           apfn[93]; /* PFN size is 174 Bytes */
  /* 0x0198 */   ULONG         unk_198[28] /* unknwon 28 */
} LDEV_WIN32K; 

Total size of LDEV_WIN32K is 0x310 Bytes This struct is alloc with the tag "Gldv"